WHY ROTI PUFFS UP?
Chapati or Roti is the most commonly used bread in Indian households, but what makes it puff up like a balloon. For that, we will need to look at a roti recipe. We need two things for making Roti – Whole wheat flour and water. Add water to flour gradually and knead it till it becomes a soft round ball. Take a tennis ball-sized pinch, dab it with the dry flour, and roll it into a flat, thin round. Please turn on the gas stove and put the Tawa/ flat griddle to make it hot. Once the Tawa is sufficiently hot, put the Roti on a hot Tawa/griddle. Cook one side first, then turn it one; it is about one-fourth cooked. Next, turn and cook the other side. This should be a little bit more cooked than the first side. Brown spots should be visible. Roti can be seen puffing, and we just added two things – flour and water. Nothing seems to be happening with the flour, but the water dissolved in the dough on being heated evaporates and forms tiny bubbles that later coalesce to form a big bubble. As Roti is closed on, edges vapors get trapped, which cause Roti to puff up, and as soon as we tear a piece from it, vapor escapes and Roti gets flattened.
Water turns into vapor as it gets heated; similarly, water from lakes, ponds, and other water bodies become vapour due to sun heat. So when we poke the puffed up Roti with the fork, we can see steam escaping.
Let us see what happens when we wrap puffed up hot Roti in foil. After a few seconds, the Roti becomes flat, and a few water droplets can be seen on the foil. The question is where this water comes from, as we know it turned into vapor. The answer to the puzzle lies in the temperature change; as soon Roti is taken off from the Tawa or heat, the water, which turned into vapor, starts cooling and turning back into the water; this process is called condensation.
The water vapor from the lake, ponds and sea rises and come in contact with the cool air of the atmosphere, which turns the vapor into the water, and it comes back to earth in the form of rain or snow; it is also called precipitation.
Why do we have a steamy bathroom mirror post hot shower?
Where does water from wet clothes go when we put it to dry in the sun?